Pipe cutting and plugging machine

ABSTRACT

A machine for cutting and plugging a pipe having a frame for clamping onto the pipe, a cutting assembly mounted on a track on the frame for movement around the pipe including a motor driving the assembly and also rotating a pair of cutting blades respectively mounted on a pair of arms, and normally urged toward each other by a spring, and a plugging assembly with a cover plate, and an arm attached to the plate and mounted for movement toward and away from the pipe. When cutting is completed an explosive charge is detonated to liberate a further spring which forces the arms apart and operates a diaphragm to permit the arm to move toward the pipe. When the plate is over the cut-off pipe, a further shaft is urged by a spring into engagement with the arm to pivot it and clamp the plate tightly onto the open end of the pipe.

United States Patent [1 1 Ortiz 1 Aug. 13, 1974 PIPE CUTTING AND PLUGGING MACHINE [76] Inventor: Angel J. Ortiz, Rio Guadalquivin 30, Mexico 5 DR, Mexico [22] Filed: Jan. 8, 1973 [21] Appl. No.: 321,990

Related US. Application Data [62] Division of Ser. No. 123,779, March 12, 1971, now

Defensive Publication No. 3,724,662.

[52] US. Cl. 29/33 R, 166/55, 251/1 [51] Int. Cl.....L E21b 29/00 [58] Field of Search 29/33 R, 33 S; 166/55;

[56] References Cited UNITED STATES PATENTS 3,603,387 9/1971 Schoeffler 166/55 Primary ExaminerGil Weidenfeld Attorney, Agent, or Firm-Cushman, Darby & Cushman ABSTRACT A machine for cutting and plugging a pipe. having a frame for clamping onto the pipe, a cutting assembly mounted on a track on the frame for movement around the pipe including a motor driving the assembly and also rotating 9. pair of cutting blades respectively mountedon a pair of arms, and normally urged toward each other by a spring, and a plugging assembly with a cover plate, and an arm attached to the plate and mounted for movement toward and away from the pipe. When cutting is completed an explosive charge is detonated to liberate a further spring which forces the arms apart and operates a diaphragm to permit the arm to move toward the pipe. When the plate is over the cut-off pipe, a further shaft is urged by a spring into engagement with the arm to pivot it and clamp the plate tightly onto the open end of the pipe.

12 Claims, 6 Drawing Figures PAIENTEDMIB 1 3.828.408

SHEET 3 OF 3 PIPE CUTTING AND PLUGGING MACHINE BRIEF DESCRIPTION OF THE PRIOR ART AND SUMMARY OF THE INVENTION This application is a division of Ser. No. 123, 779, filed Mar. 12, 1971 now US. Pat. No. 3,724,662.

The invention relates to a machine for automatically cutting and plugging a length of pipe, particularly a pipe conducting oil from an underwater or underground site.

The enormous environmental damage that even relatively small quantities of oil can cause as a result of an oil spill from a tanker or the like or from an oil well blowout underscores the need to cut off such leakage or blowout as completely and as rapidly as possible. A patent application, by the inventor of this application, Ser. No. 123,779, filed Mar. 12, 1971, describes a technique and system for use in effectively containing oil which is leaking from a tanker or from an undersea well. This technique involves the use of a flexible bag which is deployed about the source of the leak and held in place by magnetic anchors or the like for guiding oil to the surface where it is contained by a floating ring holding the top of the bag from which it can be readily and easily pumped to other tankers or the like. This system can be used in connection with tanker leaks, undersea oil leaks, etc.

In connection with stemming flow from ruptured undersea wells and the like, before this type of system or other similar systems can be effectively deployed, the pipe from the well must be cut and the end capped or plugged to minimize leakage. Because the chore must usually be done underwater and often under adverse weather conditions, it is usually a time consuming and difficult task. I

The present invention relates to a pipe cutting and plugging machine which operates automatically, effectively, quickly and completely to cut the pipe and to plug the end thereof. The machine, while it can be used for cutting and plugging pipes on land wells, finds particular utility in connection with undersea wells and is designed to be as automatic as possible and to be'easily and quickly installed and actuated by frogmen even under adverse conditions.

The machine includes a frame which is adapted to be bolted about the pipe which is to be cut at a location below where cutting is to take place. A cutting mechanism mounted on the frame includes a DC. submergible motor which engages a track extending around the frame and about the pipe for moving the motor about the pipe during cutting. The motor also drives a pair of cutter discs which are mounted on the ends of a pair of arms for movement with the motor as itcircles the pipe. A spring on a guide rod is connected to the arms to normally force them toward each other and to urge the cutting discs against the pipe as they are rotated by the motor and both the motor and discs are rotated about the pipe.

A microswitch is mounted on both of the arms to be actuated when the cutter discs cut through the pipe. The microswitches are connected to a trigger circuit for an explosive charge which is mounted in a hollow cylindrical member between the arms and the motor. The pressure wave created by the detonation of the ex- The pressure wave created by the detonation of the explosive charge is also conducted by a tube to a plenum chamber defined in a ring which extends about the pipe as part of the frame and which also serves to provide lateral support for the motor and cutting arms. The plenum chamber is in turn connected by a suitable rigid tube to a diaphragm to which is attached a shaft. At the other end of the shaft, a key portion of the shaft engages a slot in an arm which is mounted on the frame for movement toward and away from the pipe. A pipe covering plate is mounted for movement with the arm and a spring normally urges the arm and pipe covering plate toward the pipe while the key portion of the shaft attached to the diaphragm holds it in position. The explosive pressure wave transmitted to the diaphragm moves the shaft against the force exerted by a spring,

plosive charge librates a spring which engages the two arms, pulling the cutting discs away from the pipe and out of the way of the pipe covering plate.

freeing the arm which thus moves with its attached covering plate toward the cut-off pipe.

The structure which holds the arm in place and permits movement toward and away from the pipe includes a hollow shaft having a pair of opposed slots through which the arm passes. A further shaft member and a disc having a key and pushed by the shaft member are also mounted for movement in the hollow shaft and are urged in the direction of the arm by means of a spring also mounted within the hollow tube. The shaft member and disc are normallylatched in a position not engaging the arm by a pivotably mounted member which extends into a slot running along the length of the arm. When the arm has moved to a position with the attached plate over the pipe which has been cut and which is to be plugged, a stop member, such as a nut on the end of the arm, trips the pivotly mounted member, releasing the shaft member and disc which move under the urging of the spring, engaging a second slot in the arm, locking the same in place and pivoting the arm to clamp the plate firmly onto the cut-off pipe. The shaft member in the hollow tube can then be tightened by means of a spring loaded fork which can be manually pivoted to a position engaging threads on a portion of the shaft member extending out of the hollow shaft. A nut can then be manually tightened to exert additional force to more securely clamp the plate onto the cut off pipe.

Many other objects and purposes of the invention will become clear from the following detailed description of the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a perspective view of the novel machine of this application.

FIG. 2 shows a cut-away view of the embodiment of FIG. 1 embracing a pipe for cutting and plugging that pipe.

FIG. 3 shows a top view of the cutter.

FIG. 4 shows a partially cut-away perspective view of the plenum chamber defined in a ring around the frame.

FIG. 5 shows a perspective, partially cut-away view of the mechanism for causing withdrawal of the cutting discs after cutting has been completed.

FIG. 6 shows a perspective, partially cut-away view of the mechanism for releasing the arm and for causing pivoting of the arm to firmly clamp the plate onto the end of that cutoff pipe.

DETAILED DESCRIPTION OF THE DRAWINGS Reference is now made to FIGS. 1 and 2 which show one embodiment of the invention of this application. As discussed above, the machine is intended to be used primarily in cutting and plugging an undersea pipe. For effecting that operation, the pipe'is first engaged within frame which swivels open to embrace the pipe and held firmly in place by means of heavy swivel bolts 22, 24 and 26. Next, a conventional submergible, selflubricating DC. motor 28 within cylindrical housing or canister 30 is actuated by means of an encapsulated switch or any other mechanism to initiate the cutting operation. A conventional D.C. battery, which has a capacity sufficient to drive motor 28 until cutting is completed, is mounted in the interior of canister 30 as can be seen in FIG. 2 and is watertight. A plug may be provided for maintaining battery fully charged during storage.

Motor 28 is coupled by means of a conventional gear box 34, which reduces the speed of the output shaft of motor 28 to a circular track or ring 36 which runs about the pipe 40 which is to be cut. A gear 42 is driven by motor 28 via conventional speed reducing mechanism 34 and shaft 35 to cause motor 28, canister 30 and the attached cutting mechanism as described below to repeatedly rotate about pipe with the rounded end 41 of shaft 35 riding in circumferential groove 43 in the bottom of track 36.

Motor 28 also drives two cutter blade discs 42 and 44 via chains 46 and 48 in a direction opposite to the direction of rotation about pipe 40 and drive shafts 50 and gear to continually drive discs 42 and 44 at motor speed as they are also rotated at a lower speed with motor 28 about pipe 40. As can be seen in FIGS. 1 and 3, discs 42 and 44 are mounted on the ends of a pair of arms 54 and 56, respectively, which are pivotably mounted for movement about the axis of a fixed shaft member 57 which can be seen best in FIG. 5. The ends of arms 54 and 56 remote from the point of attachment to discs 42 and 44 are urged apart by a spring 58 which is mounted on a guide rod or bar 59, and spring 58 operates to continuously urge cutting discs 42 and 44 toward pipe 40 and toward each other to effect cutting.

When the two discs 42 and 44 have cut through pipe 40, they are automatically withdrawn, and a pipe clamping plate 60 automatically extended over and forced down onto the cut-off end of pipe 40. Referring to FIG. 5, in which portions of arms 54 and 56 have been removed for clarity in illustration it can be seen that a hollow cylindrical member 64 is disposed about a shaft member 57. Cylindrical member 64 is provided with two slots 66 and 68 through which extend portions 70 and 72 of piston shaft member59 which engage and hold the two outwardly extending ends 80 and 82 of a conventional spring. Spring ends 80 and 82 extend upward to engage arms 54 and 56 when liberated.

Referring to FIG. 2, a conventional push-button microswitch is mounted on the underside of each of arms 54 and 56. When both cutter discs 42 and 44 cut through pipe 40 and move inward into the pipe, the microswitch below the arm mounting the disc, for example, switch 84 on arm 54, is actuated. The actuation of this switch is sensed by a conventional trigger circuit which may be mounted in battery 32, in an arm or otherwise situated as desired. This circuitry is connected to an explosive charge 90 which is disposed as can be seen in FIG. 5 below piston shaft member 59. The detonation of explosive charge 90 operates to drive shaft member 59 upward, disengaging and liberating spring ends and 82 which move apart, engaging arms 54 and 56 and also pulling these arms apart from each other and at the same time pulling discs 42 and 44 away from pipe 40 and out of the way of the mechanism for clamping plate 60 onto the cut off end of the pipe.

As can be best seen in FIG. 5, a tube 92 is connected to a port opening into the interior of cylindrical member 64 for receiving the pressure wave created by the detonation of explosive charge after shaft 59 has moved past the port and conducting that pressure wave into a plenum chamber which extends about the periphery of a second ring or track 93 defined by frame 20. Upper ring 93 is also coupled to motor container 30 for providing lateral support for container 30. The plenum chamber within track 93 is defined by a plurality of gap seal steel strips 102 which can be best seen in FIG. 4 and which open two or three at the time as the pressure wave passes around the plenum chamber. A steel foil cap 104 rides on plenum wall applying light pressure over the gap, sealing corners on strips 102 which would be otherwise left open around the outer wall of the plenum chamber. This aids in keeping the plenum chamber pressure the instant the pressure wave occurs. The raceway ring joints can be coated with Teflon or other suitable material if desired to insure tight closure.

The pressure wave in the plenum chamber is communicated via tube 108 to the region above a conventional diaphragm 110 which moves downward urging shaft 1 12 in the same direction as the pressure wave occurs.

The wave will be adequately transmitted even if tube 108, diaphragm 110 and the plenum chamber are filled with water. As can be best seen in FIG. 6, shaft 112 terminates in its end remote from diaphragm 110 in a key portion 114 which extends upward from a block 113 into a slot 152. onthe lower surface of arm 116 for normally holding arm 116 and the attached cover plate 60 in a rest position, as illustrated in FIG. 2, away from pipe 40 during cutting. The downward movement of shaft 112 pulls key portion 114 out of the associated slot 152 on the under surface of arm 116 so that arm 1 16 is free to move toward pipe 40 under the urging of spring 117. Arm 116 and the attached cover plate 60 then move toward pipe 40 with a portion 118 of arm 116 extending slightly beyond plate 60 as can be seen in FIGS. 1 and 2 to push any pipe remaining out of the way and avoid unnecessary damage to cover 60.

Arm 1 16 is mounted for movement toward and away from pipe 40 by a holding member 120. Member 120 includes a hollow shaft portion 122 as can be seen in FIG. 6 which has a pair of opposed slots through which arm 1 16 passes, and a U-shaped portion to define at the passage of arm 116 through member 122 a pivot point for arm 116 to clamp plate 60 firmly onto pipe 40.

This clamping action is effected by a shaft which is mounted as can be seen in FIGS. 2 and 6 within hollow portion 122 for movement toward and away from arm 116. A spring 134-is also mounted about shaft 130 in hollow portion 122 and continually urges shaft 130 toward arm 116. At the end of shaft 130 which is adjacent to shaft 1 16, a further key member is provided on a disc 139 which is pushed by shaft 130 for engagenut 150 engages the upwardly extending portion of L- shaped member 142 when plate 60 is over the end of cut-off pipe 40. Member 142 then pivots about pin 146, releasing shaft 130 which moves upward pushing disc 139 until key portion 140 on disc 139 moves into a slot holding arm 116 in place and preventing rotation of the same as well as preventing covering plate 60 from moving back away from pipe 40.

The portion of shaft 116 adjacent nut 150 is cut away as shown so that it can move upward into a slot 160 of a reduced area in hollow shaft portion 120. Arm 116 is thus pivoted about member 122 to drive cover 60, which may be provided with a flexible teflon or other pipe engaging surface, tightly onto the cut off portion of pipe 40.

The above actions have all taken place after the simple activation of motor 28 by the operation of a switch or the like. The machine has itself quickly and efficiently cut off the pipe, moved the cut-off section out of the way and firmly clamped a cover plate on top of the cut off pipe section. Cover 60 can now be easily and simply tightened further if necessary by means of a spring loaded fork member 170 as shown in FIG. 2 which can be manually pivoted away from its illustrated position, to a position engaging threads on the portion of shaft 130 extending out of the end of hollow portion 120 remote from arm 1 16. By unscrewing nut 180, shaft 130 can be advanced toward arm 116 causing further pivoting and clamping plate 60 even tighter onto cut-off pipe 40. Upper threads 182 which are wound in the opposite direction can be used for withdrawing shaft 130 against the force exerted by spring 134 to reset the unit.

While the above described unit is designed and is particularly effective for use in undersea work, it can also be used effectively in plugging above ground pipes. All the moving parts in the unit can be exposed to the water and are preferably water lubricated and cooled.- The machine is designed to be used for a single use and can thereafter be discarded.

Many changes and modifications in the above described embodiment of the invention can, of course, be made without departing from the scope of the invention. Accordingly, that scope is intended to be limited only by the scope of the appended claims.

What is claimed is: g

l. A pipe cutting and plugging machine comprising: frame means for engaging a pipe to be cut, cutting means mounted on said frame means for movement around said pipe for cutting, means attached to said cutting means for causing said cutting means to engage said pipe for cutting,

motor means for operating said cutting means and causing movement of said cutting means around said pipe,

means mounted on said cutting means for sensing completion of cutting,

means connected to said sensing means for causing said cutting means to disengage from said pipe upon sensing completion of said cutting,

means mounted on said frame for movement toward and away from said pipe for plugging said pipe, and

means mounted on said frame for causing said plugging means to move to a position plugging said pipe after said cutting means is disengaged from said pipe.

2. A machine as in claim 1 wherein said cutting means includes a pair of disc blades, means connecting said motor means to said discs for rotating said discs for cutting, a pair of arms each mounting one of said discs, and means for pivotably mounting said arms and wherein said'means for causing said cutting means to engage said pipe includes spring means connected between said arms for causing'said arm to pivot and move said blades toward each other to engage said pipe.

3. A machine as in claim 2 wherein said sensing means includes switch means mounted on said arms for producing a signal upon engagement with the pipe as the blades on the arms cut through the pipe.

4. A machine as in claim 2 wherein said means for causing said cutting means to disengage includes a shaft member about which said arms pivot and having a pair of openings, a spring mounted about said shaft having upwardly extending portions for engaging the arms and forcing the arms and blades mounted thereon apart, a roughly cylindrical member mounted in said shaft member for movement about the axis of said shaft member and having a pair of outwardly extending portions protrude through said openings to normally engage said spring member and prevent said spring member from forcing. the arms apart, and an explosive charge mounted within said cylindrical member for providing a pressure wave, when said sensing means senses completion of cutting, to cause said cylindrical member to move along its axis releasing said spring member to engage said arms and force apart said blades.

5. A machine as in claim 4 wherein said plugging means includesv a plate, and an arm connected to said plate and wherein said means for causing said plugging means to move includes a member attached to said frame means for holding said arm so as to permit movement outward and away from said pipe, spring means for urging said arm and plate toward said pipe, latch means attached to said frame means for holding said arm in a rest position while cutting is taking place, means responsive to said pressure wave for releasing said latching means when said pressure wave is provided to permit said plate and arm to move outwards, stop means of said arm for engaging said member which holds said am to stop outward movement with said plate over the end of the cut pipe, means for engaging said am for pivoting said arm about said member which holds said arm to clamp said plate onto the end of said pipe.

6. A machine as in claim 5 wherein said latch means includes a diaphragm member, tube means connecting said diaphragm member to said cylindrical member for said key portion in said slot so that movement of said shaft attached to said diaphragm responsive to said pressure wave disengages said key portion from said slot to permit said arm to move toward said plate.

7. A machine as in claim wherein said stop means is a nut mounted on the end of said arm remote from said pipe.

8. A machine as in claim 5 wherein said arm holding means includes a hollow cylindrical tube having opposing slots through which said arm moves toward and away from said pipe, and wherein said arm pivoting means includes a further shaft mounted for movement in said hollow to be and having a further key portion on one end for engaging a further slot in said arm, spring 9. A machine as in claim 8 wherein said further shaft has a threaded portion extending out of the end of said hollow tube remote from said arm and further including a pivotably mounted member hollow tube for engaging said threaded portion in one position for advancing said further shaft toward said arm and increasing the clamping pressure of said plate.

10. A machine as in claim 5 wherein said arm has a portion extending beyond said plate for pushing the cut-off pipe section out of the way.

11. A machine as in claim 6 wherein said frame includes a first circular track about said pipe and a second circular track about said pipe, wherein said motor means and cutting means are mounted together for repeated rotations about said pipe with said motor means engaging said first circular track, and wherein said tube means includes means defining a plenum chamber about said second circular track, means connecting said plenum chamber to said cylindrical member and tube means connecting said diaphragm member to said plenum chamber.

12. A machine as in claim 1 wherein said frame includes a circular track about said pipe, and wherein said motor means is mounted for engaging said track and moving circularly with said cutting means around said track. 

1. A pipe cutting and plugging machine comprising: frame means for engaging a pipe to be cut, cutting means mounted on said frame means for movement around said pipe for cutting, means attached to said cutting means for causing said cutting means to engage said pipe for cutting, motor means for operating said cutting means and causing movement of said cutting means around said pipe, means mounted on said cutting means for sensing completion of cutting, means connected to said sensing means for causing said cutting means to disengage from said pipe upon sensing completion of said cutting, means mounted on said frame for movement toward and away from said pipe for plugging said pipe, and means mounted on said frame for causing said plugging means to move to a position plugging said pipe after said cutting means is disengaged from said pipe.
 2. A machine as in claim 1 wherein said cutting means includes a pair of disc blades, means connecting said motor means to said discs for rotating said discs for cutting, a pair of arms each mounting one of said discs, and means for pivotably mounting said arms and wherein said means for causing said cutting means to engage said pipe includes spring means connected between said arms for causing said arm to pivot and move said blades toward each other to engage said pipe.
 3. A machine as in claim 2 wherein said sensing means includes switch means mounted on said arms for producing a signal upon engagement with the pipe as the blades on the arms cut through the pipe.
 4. A machine as in claim 2 wherein said means for causing said cutting means to disengage includes a shaft member about which said arms pivot and having a pair of openings, a spring mounted about said shaft having upwardly extending portions for engaging the arms and forcing the arms and blades mounted thereon apart, a roughly cylindrical member mounted in said shaft member for movement about the axis of said shaft member and having a pair of outwardly extending portions protrude through said openings to normally engage said spring member and prevent said spring member from forcing the arms apart, and an explosive charge mounted within said cylindrical member for providing a pressure wave, when said sensing means senses completion of cutting, to cause said cylindrical member to move along its axis releasing said spring member to engage said arms and force apart said blades.
 5. A machine as in claim 4 wherein said plugging means includes a plate, and an arm connected to said plate and wherein said means for causing said plugging means to move includes a member attached to said frame means for holding sAid arm so as to permit movement outward and away from said pipe, spring means for urging said arm and plate toward said pipe, latch means attached to said frame means for holding said arm in a rest position while cutting is taking place, means responsive to said pressure wave for releasing said latching means when said pressure wave is provided to permit said plate and arm to move outwards, stop means of said arm for engaging said member which holds said arm to stop outward movement with said plate over the end of the cut pipe, means for engaging said arm for pivoting said arm about said member which holds said arm to clamp said plate onto the end of said pipe.
 6. A machine as in claim 5 wherein said latch means includes a diaphragm member, tube means connecting said diaphragm member to said cylindrical member for causing said diaphragm member to move in response to said pressure wave, a shaft attached to said diaphragm and having a key portion normally engaging a slot in said arm, spring means engaging said arm so as to hold said key portion in said slot so that movement of said shaft attached to said diaphragm responsive to said pressure wave disengages said key portion from said slot to permit said arm to move toward said plate.
 7. A machine as in claim 5 wherein said stop means is a nut mounted on the end of said arm remote from said pipe.
 8. A machine as in claim 5 wherein said arm holding means includes a hollow cylindrical tube having opposing slots through which said arm moves toward and away from said pipe, and wherein said arm pivoting means includes a further shaft mounted for movement in said hollow to be and having a further key portion on one end for engaging a further slot in said arm, spring means urging said further shaft to engage said further key portion with said further slot, a pivot member having a portion holding said further key portion away from said arm and a portion engaging said arm so as to release said further shaft to engage and pivot said arm.
 9. A machine as in claim 8 wherein said further shaft has a threaded portion extending out of the end of said hollow tube remote from said arm and further including a pivotably mounted member hollow tube for engaging said threaded portion in one position for advancing said further shaft toward said arm and increasing the clamping pressure of said plate.
 10. A machine as in claim 5 wherein said arm has a portion extending beyond said plate for pushing the cut-off pipe section out of the way.
 11. A machine as in claim 6 wherein said frame includes a first circular track about said pipe and a second circular track about said pipe, wherein said motor means and cutting means are mounted together for repeated rotations about said pipe with said motor means engaging said first circular track, and wherein said tube means includes means defining a plenum chamber about said second circular track, means connecting said plenum chamber to said cylindrical member and tube means connecting said diaphragm member to said plenum chamber.
 12. A machine as in claim 1 wherein said frame includes a circular track about said pipe, and wherein said motor means is mounted for engaging said track and moving circularly with said cutting means around said track. 